A standard twisting machine supports one or two yarn supplies normally constituted as yarn packages nonrotatable about a spindle axis. The yarn is pulled off the package, down through the spindle and pulled out through radially open holes at the base of the spindle adjacent a storage drum. This spindle and the storage drums are rotated at high speed and the yarn is pulled around the yarn supply to form a so-called balloon. The amount of twist imparted to the yarn is a function of the takeup speed at a takeup spool normally mounted above the yarn supply and rotated at a peripheral speed equal to the takeup speed, and the rotation speed of the spindle.
It has been known to adapt such a machine for a so-called cabling operation whereby two separate yarns, which may be of opposite twist, are wound cable-fashion around each other. Thus in the above-described type of machine the yarn supported on the spindle is not drawn down through the spindle but is drawn directly up through the takeup eye that is normally provided immediately above the spindle on the spindle axis. Another yarn is fed to the lower end of the spindle which is normally tubularly hollow, and is drawn out through the above-mentioned aperture adjacent the storage drum. This second yarn is drawn up around the package of the first yarn and through the same takeup eye. Rotation of the spindle at high speed therefore twists the yarns about each other to form a so-called double yarn of the cable type which is very useful in high-strength applications such as in carpets.
Such a machine therefore requires two separate yarn supplies. As the basic machine is a standard spinning or twisting apparatus, a separate creel is typically provided for the second yarns that are cabled around the first yarns. In most applications the second creel is provided next to but spaced by a gangway from the machine having the first yarns and the takeup spools. Each of the second yarns is led through a relatively long path beneath the gangway to the bottom of the twisting machine.
This arrangement has the considerable disadvantage that it takes up a great deal of floor space. What is more it is an extremely difficult operation to thread a new second yarn into the machine should the supply of the second yarn run out. The operator of such a machine must also keep an eye out to both sides of the gangway, checking on the takeup spools, the packs of first yarn in the basic spinning machine, and the yarn supplies in the creel for the second yarns. Furthermore while tending the creel on one side or the twisting machine on the other the operator must turn his or her back to much of the machinery so that a considerable risk of unobserved malfunctioning exists.
With all such machines another considerable problem is that threading a new yarn in is a relatively complex operation. The yarn must be painstakingly fitted into various eyes or threaded through complex guides. The operation is often aided by means of a threading hook that must be poked down onto the machine at the balloon-forming structure to pick up the free end of a new yarn. In particular the difficulty of threading in a machine having a multispindle bank can lead to interference with adjacent spinners.